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Advanced NMR approaches in the characterization of coal. Final technical report, September 1, 1990--August 31, 1993 (open access)

Advanced NMR approaches in the characterization of coal. Final technical report, September 1, 1990--August 31, 1993

This project addressed two main goals and one much smaller one. The main goals were (1) to improve the significance, reliability and information content in high-resolution NMR (nuclear magnetic resonance) characterization of coal samples and (2) to develop chemically informative NMR imaging techniques for coal. The minor goal was to explore advanced features of dynamic nuclear polarization (DNP) as a technique for coal characterization; this included the development of two DNP probes and the examination of DNP characteristics of various carbonaceous samples, including coals. {sup 13}C NMR advances for coal depended on large-sample MAS devices, employing either cross-polarization (CP) or direct polarization (DP) approaches. CP and DP spin dynamics and their relationships to quantitation and spin counting were elucidated. {sup 1}H NMR studies, based on CRAMPS, dipolar dephasing and saturation with perdeuteropyridine, led to a {sup 1}H NMR-based elucidation of chemical functionality in coal. {sup 1}H and {sup 13}C NMR imaging techniques, based on magic-angle spinning and rotating magnetic field gradients, were developed for introducing chemical shift information (hence, chemical detail) into the spatial imaging of coal. The TREV multiple-pulse sequence was found to be useful in the {sup 1}H CRAMPS imaging of samples like coal.
Date: September 30, 1993
Creator: Maciel, G. E.
Object Type: Report
System: The UNT Digital Library
Aerial Gamma Ray and Magnetic Survey, Final Report: Volume 2. Montrose Quadrangle (open access)

Aerial Gamma Ray and Magnetic Survey, Final Report: Volume 2. Montrose Quadrangle

The quadrangle includes portions of the Colorado Plateau and southern Rocky Mountains Physiographic Provinces. The entire area of the Gunnison Uplift and parts of the Uncompahgre and Sawatch Uplifts are included. A part of the Piceance Basin and a segment of the Rio Grande Rift Valley are also included. A basement complex of Precambrian metamorphic and igneous rocks is exposed in the core of the Gunnison and Sawatch Uplifts in the Southern Rocky Mountains. Jurassic and Cretaceous age sedimentary rocks lie directly on the Precambrian basement in most places. They lie on Paleozoic rocks at the west edge of the Sawatch Uplift in the north-central part of the quadrangle. Triassic beds are mapped only in the canyon of the Uncompahgre River near the southwest corner of the quadrangle. A suite of Tertiary volcanics and some sedimentary rocks occupy extensive areas. Plutonic rocks of Tertiary and laramide age occupy only a small part of the quadrangle. The literature consulted included information on about 100 separate occurrences of radioactive minerals and/or anomalous radioactivity within the quadrangle. Many fracture and stratigraphically controlled forms are reported. Most of these occurrences are clustered in three areas: Cochetopa Creek, Cebolla Creek, and Marshall Pass. Important uranium …
Date: April 1979
Creator: GeoMetrics, Inc.
Object Type: Report
System: The UNT Digital Library
Alfred A. Arraj U.S. Courthouse; Denver, Colorado: A Model of Sustainability (open access)

Alfred A. Arraj U.S. Courthouse; Denver, Colorado: A Model of Sustainability

This brochure describes the sustainability of the Alfred A. Arraj United States Courthouse in Denver, Colorado.
Date: September 1, 2005
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Annual report on the US Department of Energy`s cultural resource activities at Colorado UMTRA Project sites for October 1991--September 1992 (open access)

Annual report on the US Department of Energy`s cultural resource activities at Colorado UMTRA Project sites for October 1991--September 1992

This report summarizes the US Department of Energy`s (DOE) cultural resource studies that were undertaken in support of the DOE`s Uranium Mill Tailings Remedial Action (UMTRA) Project in the state of Colorado for the period of October 1, 1991, through September 30, 1992. This report fulfills the DOE`s obligation to provide an annual report to the state of Colorado on the status and results of cultural resource studies conducted during the above period of record. This requirement is stated in a programmatic memorandum of agreement executed between the DOE, the Advisory Council on Historic Preservation, and the Colorado State Historic Preservation Officer in December 1984. Previous reports were based on a calendar year reporting period. However, in order to be more consistent with the programmatic memorandum of agreement, the period of record for this and subsequent annual reports has been changed to the Federal fiscal year. The current status and summaries of 1992 cultural resource surveys are provided for all UMTRA Project sites in Colorado. The sites are Durango, Grand Junction, Gunnison, Maybell, Naturita, Rifle, and Slick Rock.
Date: October 6, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Approximation of continuity of lenticular Mesaverde Group sandstone lenses utilizing close-well correlations, Piceance Basin, NW Colorado. SPE 11610 (open access)

Approximation of continuity of lenticular Mesaverde Group sandstone lenses utilizing close-well correlations, Piceance Basin, NW Colorado. SPE 11610

Mesaverde Group sandstone units in 13 closely-spaced wells in the central and southern Piceance Basin of Colorado were correlated utilizing wireline log response quantitatively and qualitatively. Based on these correlations, the environmental subdivisions of the Mesaverde Group were characterized as follows: (1) paralic (upper mixed-marine) zone, occurring in the uppermost Mesaverde Group, includes thick sandstone units which are interpreted to be regionally continuous, (2) fluvial zone, containing point-bars 20 to 30+ ft thick, is interpreted to be correlatable to a maximum of 6800 ft, and (3) paludal zone has insufficient data to adequately characterize the sand units. However, 63 percent of the units are correlatable across at least 139 ft. An approximation of the dimensional characteristics of Mesaverde sandstone units has potential applications in designing hydraulic fracturing treatments and estimating gas reserves more accurately. 15 figures, 2 tables.
Date: January 1, 1982
Creator: Peterson, Richard E. & Kohout, Julie B.
Object Type: Report
System: The UNT Digital Library
Baseline Risk Assessment of Ground Water Contamination at the Uranium Mill Tailings Site Near Durango, Colorado (open access)

Baseline Risk Assessment of Ground Water Contamination at the Uranium Mill Tailings Site Near Durango, Colorado

This risk assessment evaluates the possibility of health and environmental risks from contaminated ground water at the uranium mill tailings site near Durango, Colorado. The former uranium processing site`s contaminated soil and material were removed and placed at a disposal site located in Body Canyon, Colorado, during 1986--1991 by the US Departments of Energy`s Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating the nature and extent of ground water contamination at the site. This risk assessment follows an approach similar to that used by the US Environmental Protection Agency. The first step is to determine what site-related contaminants are found in ground water samples. The next step in the risk assessment is to determine how much of these contaminants people might ingest if they got their drinking water from a well on the site. In accordance with standard practice for this type of risk assessment, the highest contaminant concentrations from the most contaminated wells are used. The risk assessment then explains the possible health problems that could result from this amount of contamination.
Date: February 1995
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Baseline Risk Assessment of Ground Water Contamination at the Uranium Mill Tailings Sites Near Slick Rock, Colorado (open access)

Baseline Risk Assessment of Ground Water Contamination at the Uranium Mill Tailings Sites Near Slick Rock, Colorado

This baseline risk assessment of ground water contamination at the uranium mill tailings sites near Slick Rock, Colorado, evaluates potential public health and environmental impacts resulting from ground water contamination at the former North Continent (NC) and Union Carbide (UC) uranium mill processing sites. The tailings at these sites will be placed in a disposal cell at the proposed Burro Canyon, Colorado, site. The US Department of Energy (DOE) anticipates the start of the first phase remedial action by the spring of 1995 under the direction of the DOE`s Uranium Mill Tailings Remedial Action (UMTRA) Project. The second phase of the UMTRA Project will evaluate ground water contamination. This baseline risk assessment is the first site-specific document for these sites under the Ground Water Project. It will help determine the compliance strategy for contaminated ground water at the site. In addition, surface water and sediment are qualitatively evaluated in this report.
Date: November 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado (open access)

Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado

This Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells. This risk assessment evaluates the most contaminated monitor wells at the processing site. It will be used to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the groundwater are cadmium, cobalt, iron, manganese, sulfate, uranium, and some of the products of radioactive decay of uranium.
Date: December 1, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado. Revision 1 (open access)

Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado. Revision 1

This report evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells to determine the potential for immediate human health and environmental impacts. This risk assessment evaluates the most contaminated groundwater that flows beneath the processing site towards the Gunnison River. The monitor wells that have consistently shown the highest concentration of most contaminants are used in this risk assessment. This risk assessment will be used in conjunction with additional activities and documents to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed …
Date: April 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Capillary discharge extreme ultraviolet lasers. [Colorado State Univ. , Ft. Collins] (open access)

Capillary discharge extreme ultraviolet lasers. [Colorado State Univ. , Ft. Collins]

The project objective is to explore the generation of soft X-ray laser radiation in a plasma column created by a fast capillary discharge. The proposed capillary lasing scheme offers the potential for compact, simple and efficient soft X-ray laser sources. For this purpose a compact, fast pulse generator which produces 100 kA current pulses with a risetime of 11 ns was constructed. Initial experiments were conducted in evacuated capillaries, in which the plasma is produced by ablation of the capillary walls. The soft X-ray emission from discharges in polyethylene capillary channels was studied to investigate the possibility of amplification in the 3-2 transition of C VI, at {lambda} = 18.2 nm. Time-resolved spectra in which this transition appears anomalously intense with respect to the 4--2 transition of the same ion were obtained. To date, however, this phenomenoa could not be confirmed as gain, as the intensity of the 18.2 nm line has not been observed to increase exponentially as a function of the capillary length. Encouraging results were obtained by fast pulse discharge excitation of capillaries filled with preionized gas. High temperature (Te > 150 eV), small diameter ({approximately}200 {mu}m) plasma columns were efficiently generated. Fast current pulse excitation of …
Date: August 1, 1992
Creator: Rocca, J. J.
Object Type: Report
System: The UNT Digital Library
Capillary discharge extreme ultraviolet lasers. Final report, December 15, 1990--February 28, 1994. Demonstration of a discharge pumped table-top soft x-ray laser (open access)
Capillary discharge extreme ultraviolet lasers. Progress report, December 15, 1991--December 14, 1992 (open access)

Capillary discharge extreme ultraviolet lasers. Progress report, December 15, 1991--December 14, 1992

The project objective is to explore the generation of soft X-ray laser radiation in a plasma column created by a fast capillary discharge. The proposed capillary lasing scheme offers the potential for compact, simple and efficient soft X-ray laser sources. For this purpose a compact, fast pulse generator which produces 100 kA current pulses with a risetime of 11 ns was constructed. Initial experiments were conducted in evacuated capillaries, in which the plasma is produced by ablation of the capillary walls. The soft X-ray emission from discharges in polyethylene capillary channels was studied to investigate the possibility of amplification in the 3-2 transition of C VI, at {lambda} = 18.2 nm. Time-resolved spectra in which this transition appears anomalously intense with respect to the 4--2 transition of the same ion were obtained. To date, however, this phenomenoa could not be confirmed as gain, as the intensity of the 18.2 nm line has not been observed to increase exponentially as a function of the capillary length. Encouraging results were obtained by fast pulse discharge excitation of capillaries filled with preionized gas. High temperature (Te > 150 eV), small diameter ({approximately}200 {mu}m) plasma columns were efficiently generated. Fast current pulse excitation of …
Date: August 1, 1992
Creator: Rocca, J. J.
Object Type: Report
System: The UNT Digital Library
Catalytic applications of mono- and dinuclear complexes containing metal-carbon sigma bonds. Final report, November 1, 1993--October 31, 1996 (open access)

Catalytic applications of mono- and dinuclear complexes containing metal-carbon sigma bonds. Final report, November 1, 1993--October 31, 1996

This report discusses results from several studies involved in the project. Investigations include: vibrational models for surface olefins and alkylidenes; mechanism of the formation and fragmentation of diosmacyclobutanes; reaction of dienes and allenes with diosmacyclobutanes; determination by nematic phase NMR of the structure of mononuclear and dinuclear ethylene complexes of osmium; and generation of ``coordinatively unsaturated`` complexes by protonation of methyl osmium complexes.
Date: December 31, 1996
Creator: Norton, J.R.
Object Type: Report
System: The UNT Digital Library
Characterization of Fly Ash From Coal Combustion (open access)

Characterization of Fly Ash From Coal Combustion

Fly ash derived from coal combustion contains predominantly spherical particles which consist of an insoluble aluminosilicate glass containing several mineral impurities. An outer layer, 50 to 300 A thick, is rich in many potentially toxic trace elements in the form of simple and complex sulfates. This layer, which is soluble in water, contains essentially all of the particulate sulfur present in fly ash in the form of sulfate. The actual mechanism(s) of formation of particulate sulfate salts are ill-defined but probably involve adsorption of condensation of gaseous sulfur species onto fly ash surfaces within the power plant stack system.
Date: January 1, 1978
Creator: Natusch, D. F.S.
Object Type: Article
System: The UNT Digital Library
Chemically Assisted in Situ Recovery of Oil Shale (open access)

Chemically Assisted in Situ Recovery of Oil Shale

The purpose of the research project was to investigate the feasibility of the chemically assisted in situ retort method for recovering shale oil from Colorado oil shale. The chemically assisted in situ procedure uses hydrogen chloride (HCl), steam (H{sub 2}O), and carbon dioxide (CO{sub 2}) at moderate pressure to recovery shale oil from Colorado oil shale at temperatures substantially lower than those required for the thermal decomposition of kerogen. The process had been previously examined under static, reaction-equilibrium conditions, and had been shown to achieve significant shale oil recoveries from powdered oil shale. The purpose of this research project was to determine if these results were applicable to a dynamic experiment, and achieve penetration into and recovery of shale oil from solid oil shale. Much was learned about how to perform these experiments. Corrosion, chemical stability, and temperature stability problems were discovered and overcome. Engineering and design problems were discovered and overcome. High recovery (90% of estimated Fischer Assay) was observed in one experiment. Significant recovery (30% of estimated Fischer Assay) was also observed in another experiment. Minor amounts of freed organics were observed in two more experiments. Penetration and breakthrough of solid cores was observed in six experiments.
Date: December 31, 1993
Creator: Ramierz, W. F.
Object Type: Report
System: The UNT Digital Library
Chemically Assisted in Situ Recovery of Oil Shale. [Quarterly Report], April 1, 1990--June 30, 1990 (open access)

Chemically Assisted in Situ Recovery of Oil Shale. [Quarterly Report], April 1, 1990--June 30, 1990

The objective of this work is to investigate, in the laboratory, the parameters associated with a chemically assisted in situ recovery procedure, using hydrogen chloride (HCI), carbon dioxide (CO{sub 2}), and steam (H{sub 2}O), to obtain-data useful to develop a process more economic than existing processes and to report all findings. The technical progress of the project is reported. The progress of the project is that experiment preparations are underway. Reactor design, process design, and experiment design have been completed. The laboratory to be used has required extensive clean-up, and is nearly ready. Safety considerations are underway. Finally, an initial literature search has revealed some important aspects that need to be considered.
Date: December 31, 1990
Creator: Ramirez, W. F.
Object Type: Report
System: The UNT Digital Library
Chemically Assisted in Situ Recovery of Oil Shale. [Quarterly] Report, April 1, 1993--June 30, 1993 (open access)

Chemically Assisted in Situ Recovery of Oil Shale. [Quarterly] Report, April 1, 1993--June 30, 1993

The objective of this work is to investigate, in the laboratory, the parameters associated with a chemically assisted in situ recovery procedure, using hydrogen chloride (HCI), carbon dioxide (CO{sub 2}), and steam (H{sub 2}0), to obtain data useful to develop a process more economic than existing processes and to report all findings. The technical progress of the project is reported. The project status is that the progress is being made towards being able to run meaningful experiments.
Date: September 1, 1993
Creator: Ramirez, W. F.
Object Type: Report
System: The UNT Digital Library
Chemically Assisted in Situ Recovery of Oil Shale. [Quarterly Report], October 1, 1991--December 31, 1991 (open access)

Chemically Assisted in Situ Recovery of Oil Shale. [Quarterly Report], October 1, 1991--December 31, 1991

The objective of this work is to investigate, in the laboratory, the parameters associated with a chemically assisted in situ recovery procedure, using hydrogen chloride (HCI), carbon dioxide (CO{sub 2}), and steam (H{sub 2}O), to obtain data useful to develop a process more economic than existing processes and to report all findings. The technical progress of the project is reported. The project status is that the solutions to the problems discussed in the third quarter status, were found to function satisfactorily. Future needs have been considered, and appropriate equipment and instrumentation changes have been designed. Only one experiment was performed this quarter, with some improvement over the previous experiments. The increase in shale oil recovery followed directly from the changes discussed last quarter, but the improvement could have been larger with wider-spread implementation of the changes. Equipment was purchased to rectify the need, and will be installed shortly. Further, a minor change in the design was necessary to account for the brittleness of high temperature electrical resistance heating tapes. The focus of the work this quarter has been on the development of computer software to enable the use of on-line parameter identification, the design of the instrumentation necessary to adequately …
Date: December 31, 1991
Creator: Ramirez, W. F.
Object Type: Report
System: The UNT Digital Library
Chemically Assisted in Situ Recovery of Oil Shale. Technical Progress Report, April 1, 1991--June 30, 1991 (open access)

Chemically Assisted in Situ Recovery of Oil Shale. Technical Progress Report, April 1, 1991--June 30, 1991

The objective of this work is to investigate, in the laboratory, the parameters associated with a chemically assisted in situ recovery procedure, using hydrogen chloride (HCI), carbon dioxide (CO{sub 2}), and steam (H{sub 2}O), to obtain data useful to develop a process more economic than existing processes and to report all findings. Quarter summary: all modifications previously planned where completed and a reaction experiment was run. A couple design flaws were discovered, improvements were designed, and all parts are expected in the first week of July. Experiment {number_sign}6 is expected to run the following Monday. Barring further mishap, experiments will be run one each week thereafter. The project is behind schedule, but the project is well positioned to make significant and considerable progress.
Date: December 1, 1991
Creator: Ramirez, W. F.
Object Type: Report
System: The UNT Digital Library
Chemically modified electrodes and related solution studies (open access)

Chemically modified electrodes and related solution studies

This report is divided into 5 sections: Ru[sub 4]/Fe complexes of tetra(4[prime]-methyl-2,2[prime]-bipyridine)porphyrin--catalytic epoxidation of olefins; water oxidation catalysis by doubly linked [mu]-oxo ruthenium complexes; polymer films formed by oxidation of transition metal electrodes into solutions of bisbipyridinealkane ligands; polymer films containing [CpMo([mu]-S)][sub 2]S[sub 2]CHR dinuclear clusters;and conducting polymer films for catalyst incorporation.
Date: April 1, 1993
Creator: Elliott, C.M.
Object Type: Report
System: The UNT Digital Library
Chemically modified electrodes and related solution studies. Final technical report, January 15, 1991--January 14, 1992 (open access)

Chemically modified electrodes and related solution studies. Final technical report, January 15, 1991--January 14, 1992

This report is divided into 5 sections: Ru{sub 4}/Fe complexes of tetra(4{prime}-methyl-2,2{prime}-bipyridine)porphyrin--catalytic epoxidation of olefins; water oxidation catalysis by doubly linked {mu}-oxo ruthenium complexes; polymer films formed by oxidation of transition metal electrodes into solutions of bisbipyridinealkane ligands; polymer films containing [CpMo({mu}-S)]{sub 2}S{sub 2}CHR dinuclear clusters;and conducting polymer films for catalyst incorporation.
Date: April 1, 1993
Creator: Elliott, C. M.
Object Type: Report
System: The UNT Digital Library
Colorado: basic data for thermal springs and wells as recorded in GEOTHERM (open access)

Colorado: basic data for thermal springs and wells as recorded in GEOTHERM

GEOTHERM sample file contains 225 records for Colorado. Three computer-generated indexes are found in appendices A, B, and C of this report. The indexes give one line summaries of each GEOTHERM record describing the chemistry of geothermal springs and wells in the sample file for Colorado. Each index is sorted by different variables to assist the user in locating geothermal records describing specific sites. Appendix A is sorted by the county name and the name of the source. Also given are latitude, longitude (both use decimal minutes), township, range, section, GEOTHERM record identifier, and temperature (/sup 0/C). Appendix B is sorted by county, township, range, and section. Also given are name of source, GEOTHERM record identifier, and temperature (/sup 0/C). Appendix C is first sorted into one-degree blocks by latitude, and longitude, and then by name of source. Adjacent one-degree blocks which are published as a 1:250,000 map are combined under the appropriate map name. Also given are GEOTHERM record identifier, and temperature (/sup 0/C). A bibliography is given in Appendix D.
Date: May 1, 1983
Creator: Bliss, J. D.
Object Type: Report
System: The UNT Digital Library
Colorado: Colorado's Clean Energy Resources and Economy (Brochure) (open access)

Colorado: Colorado's Clean Energy Resources and Economy (Brochure)

This document highlights the Office of Energy Efficiency and Renewable Energy's investments and impacts in the state of Colorado.
Date: March 1, 2013
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Colorado Economic Impact Study on the Uranium Mill Tailings Remedial Action Project in Colorado: Colorado State Fiscal Year 1993 (open access)

Colorado Economic Impact Study on the Uranium Mill Tailings Remedial Action Project in Colorado: Colorado State Fiscal Year 1993

The Colorado economic impact study summarizes employment and economic benefits to the state from activities associated with the Uranium Mill Tailings Remedial Action (UMTRA) Project during Colorado state fiscal year (FY) 1993. To capture employment benefits, a questionnaire was distributed to subcontractor employees at the active UMTRA Project sites of Grand Junction, Rifle, and Gunnison, Colorado. An estimated 52 percent of the employees working on the UMTRA Project responded to this information request. Economic data were requested from each prime subcontractor, as well as from the Remedial Action Contractor. The most significant benefits associated with the UMTRA Project in Colorado are: Direct employment was estimated at 894 workers; An estimated 89 percent of all direct employment was local; Secondary employment resulting from remedial action at the active Colorado UMTRA Project sites and the Grand Junction vicinity property program is estimated at 546 workers. Total employment (direct and secondary) is estimated at 1440 workers for the period of study (July 1, 1992, to June 30, 1993). An estimated $24.1 million was paid in wages to UMTRA workers in Colorado during FY1993; Direct and secondary wage earnings were estimated at $39.9 million; Income tax payments to the state of Colorado were estimated …
Date: November 12, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library